Rocking grate.



PATENTBD 00T.I 22.1907.

G. G. ANDREWS.

ROGKING GRATE.

APPLIOATIQN FILED HAR. z2,

GEORGE C. ANDREWS, OF MINNEAPOLIS, MINNESOTA.

ROCKING GRATE.

Speeiiieaton of Letters Patent.

Patented Oct. 22, 1907.

Application filed March 22,1906. Serial No. 307,374:-

To all 'whom it 'muy concern:

Be it known that I, GEORGE G. ANDREWS, a citizen of the United States, residing at Minneapolis, in the county of Hennepin and State of Minnesota, have invented certain `new and useiul Improvements in Roeking Gratos; and l do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention has ior its object to provide an improved grate especially adapted for use in connection with upright boi 1ers such as used in hot water and steam heating systems, and to this vend it consists of the novel devices and combinations of devices hereinafter` described and delued in the claims.

The invention `is illustrated in the accompanying drawings, wherein like characters indicate like parts throughout the several views.

Figure Il is a horizontal section taken through a boiler on the line x a" of Fig. 2, and showing my improved grate applied thereto, some parts being broken away; and Fig. 2 is a vertical section taken through the boiler on the line x2 x2 of Fig. l, the upper portion of the boiler being broken away.

The numeral l indicates the outer shell of the boiler,

' the same being of cylindrical iorm and having the usual ,8 through which nutted bolts 9 are passed.

door opening 2 in one side of its lower portion, which opens into the ash pit 3.

The numeral :l indicates the inner shell or fire-box of the boiler between which and the outer shell of the boiler the Water eliamber 5 is formed, the lower portion of said inner shell 4 being spaced apart from the shell l, by means oi the usual mud ring 6.

My improved grate involves an expansible and contracl'ible grate supporting ring 7 preferably formed in two sections the ends of said sections being overlapped and having coincident circumferentially extended slots Each ring section has a pair oi supporting feet l0 that extend radially outward therefrom, and at their extremities are turned downward and are adapted to be rigidly but detach-ably secured to the boiler shell 1, by nutted belts ll.. The grate proper is made up oi two long toothed grate bars l2, and two or more relatively short toothed grate bars 13. The long grate bars l2 have short trunnions 14, and long trunnions l5 that rest in notches or open seats 1G formed in the sectional supporting ring 7. The said long trunnions l5 are also passed outward through perforations in the outer shell l, and terminate in angular portions I5 to which a detachable shaker lever (not shown) is adapted to be applied. The short grate sections L3, at both ends, have short trunnions 17 that rest in notches or open seats 18 formed in the sectional supporting ring 7. The long grate sections l2 are provided with depending arms 19 and the short grate sections 13 are provided with similar depending arms 20. The arms 19 of the long grate sections are connected by links 2l in the arms 2() of the short grate sections 13 that are on the same side of the center of the complete grate, and of the supporting ring 7. The connected arms 19 and 20 expand parallel to each other, so that when one of the long grates l2 is rocked, a corresponding rocking movement will be imparted to the short grate on the same side therewith. It will thus be seen that one half of the complete grate Will be moved by rocking one oi the long grates, and that the other half of the grates will be moved by rocking of the said long grates. When the grate supporting ring 7 is secured in the Working position shown in the drawings, the grate sections may be removed individually from working positions, or placed individually in Working positions. The short gratos may be raised directly upward from and out of their seats and the grate supporting ring, but to remove the long grates, one end thereof must be raised and aslight endwise movement imparted thereto, in order to withdraw the long trunnions l5 from the perforations in the shell l. As shown,

the links 21 are detachably pivoted to the arms 19 and 20 by means of pins 22 that are held in place by cottors 23.

In applying the grate supporting ring 7 in working position, or in removing it therefrom, the nutted bolts 9 are loosened, so that the two 'ring sections can be iorced together or contracted, thereby carrying the feet l() away from the inner surface of the boiler shell l, thus making it an easy matter to move said ring vertically within the ash pit portion oi the boiler. In the application or removal of the said ring after the boiler is set up, it is necessary to remove the nutted bolts 9, thereby disconnecting the sections of the said ring, so that they may be passed separately through the door opening 2. When the said ring is placed in working position, and its feet l0 are secured to the boiler shell l by means of the nutted bolts ll, the nutted bolts 9 should be tightened, thereby rmly clamping together the overlapped ends of the sections of said ring.

In the construction oi boilers having cylindrical shells, it usually happens that the said shells are not perfectly cylindrical or round in cross section. The expansible and contractible grate supporting ring, however, makes it possible to securely clamp the supporting ieet thereof, against the surface of a boiler shell that varies considerably in cross section from true cylindri cal form.

The perforations in the shell l through which the long trunnions l5 of the grate sections l2 are passed, are necessai-ily made considerably larger than the said trunnions, so as to permit the grates to be inserted by an endwise rocking movement, as above described. To keep the joint around the said trunnions tight, I preferaloly provide a flexible thin metal plate 24 which is secured to the exterior ot the shell l, and the perforations of which closely lit the said trunnions l5.

This improved grate is of small cost, may be very easily and quickly applied in Working position or removed therefrom, and when placed in Working position, affords an extremely efficient grate. The act that only one half of the grate is moved at one time in shaking down the ashes, gives the least possible disturbance to the bed of coals, and furthermore, makes the grato very easy to operate.

What I claim is:

1. The combination with a boiler having an approximately cylindrical fire box, of a sectional circumferentially expansible grate supporting' ring, legs or spacing projections connecting the sections of said ring to the said boiler', ol' a plurality of toothed grate bars lnounted on and supported by said supportingl ring, substantially as described.

2. The combination with a cylindrical boiler, of a sectional lgrate supporting ring,` 7 having supportingl feet l() and overlapped ends formed with slots S, nutted bolts Working through said slots 8 for clamping the overlapped ends of said grate sections together, and a plurality of toothed grate sections l2 and 13 detachably mounted on and supported by said supportingring 7, substantially as described.

ln testimony whereof I allix my signature in presence of two Witnesses.

GEORGE C. ANDnEWs.

Witnesses Mann-1 Hom., F. D. MERCHANT. 

